Skin cells lecture - week 2 Flashcards
What is the hypodermic/ subcutis?
- mature adipose tissue
- compartmentalised by fibrous septa
- thickness and degree of compartmentalisation variable
what is the dermis?
- bundles of collagen fibres and strands of elastic fibres
- small amount of acellular ground substance
- 2 layers - reticular and papillary
How man y layers of the epidermis are there?
six
Name all six layers of the epidermis
- top
- stratum corneum
- stratum granulosum
- stratum spinosum
- stratum basale
- bottom
name four cells of the epidermis
- keratinocytes
- langerhans cells
- melanocytes
- Merkel cell
What is the function of keratinocytes?
production of protective keratin layer
What is the function of langerhans cells?
antigen presentation
What is the function of melanocytes?
melanin, UV protection
What is the function of Merkel cells?
rare neuroendocrine cells - sensory
what are hair follicles?
composed of several layers
always associated with sebaceous glands and arrestor pili
What are sebaceous glands?
- secretes sebum (oily substances)
- holocrine mechanism of secretion
- lubricates hair and skin
What are eccrine sweat glands and ducts?
- secretly component (highly coiled) and duct (stragiht)
- outer layer of contractile cells (myoepithelial cells)
- secrete sweat - mostly water, sodium and chloride ions, urea
what are the functions of skin?
- protection form multiple external threats - UV/ mechanical/ biological/ chemical
- moisture control
- immunological/ antigen presentation
- metabolic (eg. vitamin D/ lipid reservoir)
- thermoregulation
- sensory
- excretory
What are the functions of the eccrine (sweat) gland?
thermoregulation and excretory
What are the functions of the hypodermis?
- thermoregulation
- metabolic (lipid storage)
- protection - mechanical (cushioning)
